Mix cake mix and strawberry soda for 2 minutes. Divide the cake batter between 24 lined muffin cups. Bake at 350 degrees for 19-23 minutes.

Beat butter, shortening and vanilla until creamy.

Add powdered sugar, 1 cup at a time, beating after each cup.

Beat in 1/2 cup heavy cream until light and fluffy. If necessary, add additional heavy cream, 1 tablespoon at a time until it is the consistency you want.

Paint the inside of a pastry bag, fitted with a large star tit, with stripes of gel paste food coloring: two blue and two red.

Spoon buttercream into pastry bag and pipe onto cupcake.

When color runs out, repeat the process until all of the cupcakes are frosted.